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/* LRA (local register allocator) driver and LRA utilities. Copyright (C) 2010-2025 Free Software Foundation, Inc. Contributed by Vladimir Makarov <vmakarov@redhat.com>. This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see <http://www.gnu.org/licenses/>. */ /* The Local Register Allocator (LRA) is a replacement of former reload pass. It is focused to simplify code solving the reload pass tasks, to make the code maintenance easier, and to implement new perspective optimizations. The major LRA design solutions are: o division small manageable, separated sub-tasks o reflection of all transformations and decisions in RTL as more as possible o insn constraints as a primary source of the info (minimizing number of target-depended macros/hooks) In brief LRA works by iterative insn process with the final goal is to satisfy all insn and address constraints: o New reload insns (in brief reloads) and reload pseudos might be generated; o Some pseudos might be spilled to assign hard registers to new reload pseudos; o Recalculating spilled pseudo values (rematerialization); o Changing spilled pseudos to stack memory or their equivalences; o Allocation stack memory changes the address displacement and new iteration is needed. Here is block diagram of LRA passes: ------------------------ --------------- | Undo inheritance for | --------------- | Memory-memory | | spilled pseudos, | | New (and old) | | move coalesce |<---| splits for pseudos got |<-- | pseudos | --------------- | the same hard regs, | | assignment | Start | | and optional reloads | --------------- | | ------------------------ ^ V | ---------------- | ----------- V | Update virtual | | | Remove |----> ------------>| register | | | scratches | ^ | displacements | | ----------- | ---------------- | | | | | V New | | ------------ pseudos ------------------- | |Constraints:| or insns | Inheritance/split | | | RTL |--------->| transformations | | | transfor- | | in EBB scope | | substi- | mations | ------------------- | tutions ------------ | | No change ---------------- V | Spilled pseudo | ------------------- | to memory |<----| Rematerialization | | substitution | ------------------- ---------------- | No susbtitions V ------------------------- | Hard regs substitution, | | devirtalization, and |------> Finish | restoring scratches got | | memory | ------------------------- To speed up the process: o We process only insns affected by changes on previous iterations; o We don't use DFA-infrastructure because it results in much slower compiler speed than a special IR described below does; o We use a special insn representation for quick access to insn info which is always *synchronized* with the current RTL; o Insn IR is minimized by memory. It is divided on three parts: o one specific for each insn in RTL (only operand locations); o one common for all insns in RTL with the same insn code (different operand attributes from machine descriptions); o one oriented for maintenance of live info (list of pseudos). o Pseudo data: o all insns where the pseudo is referenced; o live info (conflicting hard regs, live ranges, # of references etc); o data used for assigning (preferred hard regs, costs etc). This file contains LRA driver, LRA utility functions and data, and code for dealing with scratches. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "backend.h" #include "target.h" #include "rtl.h" #include "rtl-error.h" #include "tree.h" #include "predict.h" #include "df.h" #include "memmodel.h" #include "tm_p.h" #include "optabs.h" #include "regs.h" #include "ira.h" #include "recog.h" #include "expr.h" #include "cfgrtl.h" #include "cfgbuild.h" #include "lra.h" #include "lra-int.h" #include "print-rtl.h" #include "function-abi.h" /* Dump bitmap SET with TITLE and BB INDEX. */ void lra_dump_bitmap_with_title (const char *title, bitmap set, int index) { unsigned int i; int count; bitmap_iterator bi; static const int max_nums_on_line = 10; if (bitmap_empty_p (set)) return; fprintf (lra_dump_file, " %s %d:", title, index); fprintf (lra_dump_file, "\n"); count = max_nums_on_line + 1; EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) { if (count > max_nums_on_line) { fprintf (lra_dump_file, "\n "); count = 0; } fprintf (lra_dump_file, " %4u", i); count++; } fprintf (lra_dump_file, "\n"); } /* Hard registers currently not available for allocation. It can changed after some hard registers become not eliminable. */ HARD_REG_SET lra_no_alloc_regs; static int get_new_reg_value (void); static void expand_reg_info (void); static void invalidate_insn_recog_data (int); static int get_insn_freq (rtx_insn *); static void invalidate_insn_data_regno_info (lra_insn_recog_data_t, rtx_insn *, int); /* Expand all regno related info needed for LRA. */ static void expand_reg_data (int old) { resize_reg_info (); expand_reg_info (); ira_expand_reg_equiv (); for (int i = (int) max_reg_num () - 1; i >= old; i--) lra_change_class (i, ALL_REGS, " Set", true); } /* Create and return a new reg of ORIGINAL mode. If ORIGINAL is NULL or of VOIDmode, use MD_MODE for the new reg. Initialize its register class to RCLASS. Print message about assigning class RCLASS containing new register name TITLE unless it is NULL. Use attributes of ORIGINAL if it is a register. The created register will have unique held value. */ rtx lra_create_new_reg_with_unique_value (machine_mode md_mode, rtx original, enum reg_class rclass, HARD_REG_SET *exclude_start_hard_regs, const char *title) { machine_mode mode; rtx new_reg; if (original == NULL_RTX || (mode = GET_MODE (original)) == VOIDmode) mode = md_mode; lra_assert (mode != VOIDmode); new_reg = gen_reg_rtx (mode); if (original == NULL_RTX || ! REG_P (original)) { if (lra_dump_file != NULL) fprintf (lra_dump_file, " Creating newreg=%i", REGNO (new_reg)); } else { if (ORIGINAL_REGNO (original) >= FIRST_PSEUDO_REGISTER) ORIGINAL_REGNO (new_reg) = ORIGINAL_REGNO (original); REG_USERVAR_P (new_reg) = REG_USERVAR_P (original); REG_POINTER (new_reg) = REG_POINTER (original); REG_ATTRS (new_reg) = REG_ATTRS (original); if (lra_dump_file != NULL) fprintf (lra_dump_file, " Creating newreg=%i from oldreg=%i", REGNO (new_reg), REGNO (original)); } if (lra_dump_file != NULL) { if (title != NULL) fprintf (lra_dump_file, ", assigning class %s to%s%s r%d", reg_class_names[rclass], *title == '\0' ? "" : " ", title, REGNO (new_reg)); fprintf (lra_dump_file, "\n"); } expand_reg_data (max_reg_num ()); setup_reg_classes (REGNO (new_reg), rclass, NO_REGS, rclass); if (exclude_start_hard_regs != NULL) lra_reg_info[REGNO (new_reg)].exclude_start_hard_regs = *exclude_start_hard_regs; return new_reg; } /* Analogous to the previous function but also inherits value of ORIGINAL. */ rtx lra_create_new_reg (machine_mode md_mode, rtx original, enum reg_class rclass, HARD_REG_SET *exclude_start_hard_regs, const char *title) { rtx new_reg; new_reg = lra_create_new_reg_with_unique_value (md_mode, original, rclass, exclude_start_hard_regs, title); if (original != NULL_RTX && REG_P (original)) lra_assign_reg_val (REGNO (original), REGNO (new_reg)); return new_reg; } /* Set up for REGNO unique hold value. */ void lra_set_regno_unique_value (int regno) { lra_reg_info[regno].val = get_new_reg_value (); } /* Invalidate INSN related info used by LRA. The info should never be used after that. */ void lra_invalidate_insn_data (rtx_insn *insn) { lra_invalidate_insn_regno_info (insn); invalidate_insn_recog_data (INSN_UID (insn)); } /* Mark INSN deleted and invalidate the insn related info used by LRA. */ void lra_set_insn_deleted (rtx_insn *insn) { lra_invalidate_insn_data (insn); SET_INSN_DELETED (insn); } /* Delete an unneeded INSN and any previous insns who sole purpose is loading data that is dead in INSN. */ void lra_delete_dead_insn (rtx_insn *insn) { rtx_insn *prev = prev_real_insn (insn); rtx prev_dest; /* If the previous insn sets a register that dies in our insn, delete it too. */ if (prev && GET_CODE (PATTERN (prev)) == SET && (prev_dest = SET_DEST (PATTERN (prev)), REG_P (prev_dest)) && reg_mentioned_p (prev_dest, PATTERN (insn)) && find_regno_note (insn, REG_DEAD, REGNO (prev_dest)) && ! side_effects_p (SET_SRC (PATTERN (prev)))) lra_delete_dead_insn (prev); lra_set_insn_deleted (insn); } /* Emit insn x = y + z. Return NULL if we failed to do it. Otherwise, return the insn. We don't use gen_add3_insn as it might clobber CC. */ static rtx_insn * emit_add3_insn (rtx x, rtx y, rtx z) { rtx_insn *last; last = get_last_insn (); if (have_addptr3_insn (x, y, z)) { rtx_insn *insn = gen_addptr3_insn (x, y, z); /* If the target provides an "addptr" pattern it hopefully does for a reason. So falling back to the normal add would be a bug. */ lra_assert (insn != NULL_RTX); emit_insn (insn); return insn; } rtx_insn *insn = emit_insn (gen_rtx_SET (x, gen_rtx_PLUS (GET_MODE (y), y, z))); if (recog_memoized (insn) < 0) { delete_insns_since (last); insn = NULL; } return insn; } /* Emit insn x = x + y. Return the insn. We use gen_add2_insn as the last resort. */ static rtx_insn * emit_add2_insn (rtx x, rtx y) { rtx_insn *insn = emit_add3_insn (x, x, y); if (insn == NULL_RTX) { insn = gen_add2_insn (x, y); if (insn != NULL_RTX) emit_insn (insn); } return insn; } /* Target checks operands through operand predicates to recognize an insn. We should have a special precaution to generate add insns which are frequent results of elimination. Emit insns for x = y + z. X can be used to store intermediate values and should be not in Y and Z when we use X to store an intermediate value. Y + Z should form [base] [+ index[ * scale]] [ + disp] where base and index are registers, disp and scale are constants. Y should contain base if it is present, Z should contain disp if any. index[*scale] can be part of Y or Z. */ void lra_emit_add (rtx x, rtx y, rtx z) { int old; rtx_insn *last; rtx a1, a2, base, index, disp, scale, index_scale; bool ok_p; rtx_insn *add3_insn = emit_add3_insn (x, y, z); old = max_reg_num (); if (add3_insn != NULL) ; else { disp = a2 = NULL_RTX; if (GET_CODE (y) == PLUS) { a1 = XEXP (y, 0); a2 = XEXP (y, 1); disp = z; } else { a1 = y; if (CONSTANT_P (z)) disp = z; else a2 = z; } index_scale = scale = NULL_RTX; if (GET_CODE (a1) == MULT) { index_scale = a1; index = XEXP (a1, 0); scale = XEXP (a1, 1); base = a2; } else if (a2 != NULL_RTX && GET_CODE (a2) == MULT) { index_scale = a2; index = XEXP (a2, 0); scale = XEXP (a2, 1); base = a1; } else { base = a1; index = a2; } if ((base != NULL_RTX && ! (REG_P (base) || GET_CODE (base) == SUBREG)) || (index != NULL_RTX && ! (REG_P (index) || GET_CODE (index) == SUBREG)) || (disp != NULL_RTX && ! CONSTANT_P (disp)) || (scale != NULL_RTX && ! CONSTANT_P (scale))) { /* Probably we have no 3 op add. Last chance is to use 2-op add insn. To succeed, don't move Z to X as an address segment always comes in Y. Otherwise, we might fail when adding the address segment to register. */ lra_assert (x != y && x != z); emit_move_insn (x, y); rtx_insn *insn = emit_add2_insn (x, z); lra_assert (insn != NULL_RTX); } else { if (index_scale == NULL_RTX) index_scale = index; if (disp == NULL_RTX) { /* Generate x = index_scale; x = x + base. */ lra_assert (index_scale != NULL_RTX && base != NULL_RTX); emit_move_insn (x, index_scale); rtx_insn *insn = emit_add2_insn (x, base); lra_assert (insn != NULL_RTX); } else if (scale == NULL_RTX) { /* Try x = base + disp. */ lra_assert (base != NULL_RTX); last = get_last_insn (); rtx_insn *move_insn = emit_move_insn (x, gen_rtx_PLUS (GET_MODE (base), base, disp)); if (recog_memoized (move_insn) < 0) { delete_insns_since (last); /* Generate x = disp; x = x + base. */ emit_move_insn (x, disp); rtx_insn *add2_insn = emit_add2_insn (x, base); lra_assert (add2_insn != NULL_RTX); } /* Generate x = x + index. */ if (index != NULL_RTX) { rtx_insn *insn = emit_add2_insn (x, index); lra_assert (insn != NULL_RTX); } } else { /* Try x = index_scale; x = x + disp; x = x + base. */ last = get_last_insn (); rtx_insn *move_insn = emit_move_insn (x, index_scale); ok_p = false; if (recog_memoized (move_insn) >= 0) { rtx_insn *insn = emit_add2_insn (x, disp); if (insn != NULL_RTX) { if (base == NULL_RTX) ok_p = true; else { insn = emit_add2_insn (x, base); if (insn != NULL_RTX) ok_p = true; } } } if (! ok_p) { rtx_insn *insn; delete_insns_since (last); /* Generate x = disp; x = x + base; x = x + index_scale. */ emit_move_insn (x, disp); if (base != NULL_RTX) { insn = emit_add2_insn (x, base); lra_assert (insn != NULL_RTX); } insn = emit_add2_insn (x, index_scale); lra_assert (insn != NULL_RTX); } } } } /* Functions emit_... can create pseudos -- so expand the pseudo data. */ if (old != max_reg_num ()) expand_reg_data (old); } /* The number of emitted reload insns so far. */ int lra_curr_reload_num; static void remove_insn_scratches (rtx_insn *insn); /* Emit x := y, processing special case when y = u + v or y = u + v * scale + w through emit_add (Y can be an address which is base + index reg * scale + displacement in general case). X may be used as intermediate result therefore it should be not in Y. */ void lra_emit_move (rtx x, rtx y) { int old; rtx_insn *insn; if (GET_CODE (y) != PLUS) { if (rtx_equal_p (x, y)) return; old = max_reg_num (); insn = (GET_CODE (x) != STRICT_LOW_PART ? emit_move_insn (x, y) : emit_insn (gen_rtx_SET (x, y))); /* The move pattern may require scratch registers, so convert them into real registers now. */ if (insn != NULL_RTX) remove_insn_scratches (insn); if (REG_P (x)) lra_reg_info[ORIGINAL_REGNO (x)].last_reload = ++lra_curr_reload_num; /* Function emit_move can create pseudos -- so expand the pseudo data. */ if (old != max_reg_num ()) expand_reg_data (old); return; } lra_emit_add (x, XEXP (y, 0), XEXP (y, 1)); } /* Update insn operands which are duplication of operands whose numbers are in array of NOPS (with end marker -1). The insn is represented by its LRA internal representation ID. */ void lra_update_dups (lra_insn_recog_data_t id, signed char *nops) { int i, j, nop; struct lra_static_insn_data *static_id = id->insn_static_data; for (i = 0; i < static_id->n_dups; i++) for (j = 0; (nop = nops[j]) >= 0; j++) if (static_id->dup_num[i] == nop) *id->dup_loc[i] = *id->operand_loc[nop]; } /* Report asm insn error and modify the asm insn. */ void lra_asm_insn_error (rtx_insn *insn) { lra_asm_error_p = true; error_for_asm (insn, "%<asm%> operand has impossible constraints" " or there are not enough registers"); /* Avoid further trouble with this insn. */ if (JUMP_P (insn)) { ira_nullify_asm_goto (insn); lra_invalidate_insn_data (insn); } else { PATTERN (insn) = gen_rtx_USE (VOIDmode, const0_rtx); lra_set_insn_deleted (insn); } } /* This page contains code dealing with info about registers in the insns. */ /* Pools for insn reg info. */ object_allocator<lra_insn_reg> lra_insn_reg_pool ("insn regs"); /* Create LRA insn related info about a reference to REGNO in INSN with TYPE (in/out/inout), biggest reference mode MODE, flag that it is reference through subreg (SUBREG_P), and reference to the next insn reg info (NEXT). If REGNO can be early clobbered, alternatives in which it can be early clobbered are given by EARLY_CLOBBER_ALTS. */ static struct lra_insn_reg * new_insn_reg (rtx_insn *insn, int regno, enum op_type type, machine_mode mode, bool subreg_p, alternative_mask early_clobber_alts, struct lra_insn_reg *next) { lra_insn_reg *ir = lra_insn_reg_pool.allocate (); ir->type = type; ir->biggest_mode = mode; if (NONDEBUG_INSN_P (insn)) lra_update_biggest_mode (regno, mode); ir->subreg_p = subreg_p; ir->early_clobber_alts = early_clobber_alts; ir->regno = regno; ir->next = next; return ir; } /* Free insn reg info list IR. */ static void free_insn_regs (struct lra_insn_reg *ir) { struct lra_insn_reg *next_ir; for (; ir != NULL; ir = next_ir) { next_ir = ir->next; lra_insn_reg_pool.remove (ir); } } /* Finish pool for insn reg info. */ static void finish_insn_regs (void) { lra_insn_reg_pool.release (); } /* This page contains code dealing LRA insn info (or in other words LRA internal insn representation). */ /* Map INSN_CODE -> the static insn data. This info is valid during all translation unit. */ struct lra_static_insn_data *insn_code_data[NUM_INSN_CODES]; /* Debug insns are represented as a special insn with one input operand which is RTL expression in var_location. */ /* The following data are used as static insn operand data for all debug insns. If structure lra_operand_data is changed, the initializer should be changed too. */ static struct lra_operand_data debug_operand_data = { NULL, /* alternative */ 0, /* early_clobber_alts */ E_VOIDmode, /* We are not interesting in the operand mode. */ OP_IN, 0, 0, 0 }; /* The following data are used as static insn data for all debug bind insns. If structure lra_static_insn_data is changed, the initializer should be changed too. */ static struct lra_static_insn_data debug_bind_static_data = { &debug_operand_data, 0, /* Duplication operands #. */ -1, /* Commutative operand #. */ 1, /* Operands #. There is only one operand which is debug RTL expression. */ 0, /* Duplications #. */ 0, /* Alternatives #. We are not interesting in alternatives because we does not proceed debug_insns for reloads. */ NULL, /* Hard registers referenced in machine description. */ NULL /* Descriptions of operands in alternatives. */ }; /* The following data are used as static insn data for all debug marker insns. If structure lra_static_insn_data is changed, the initializer should be changed too. */ static struct lra_static_insn_data debug_marker_static_data = { &debug_operand_data, 0, /* Duplication operands #. */ -1, /* Commutative operand #. */ 0, /* Operands #. There isn't any operand. */ 0, /* Duplications #. */ 0, /* Alternatives #. We are not interesting in alternatives because we does not proceed debug_insns for reloads. */ NULL, /* Hard registers referenced in machine description. */ NULL /* Descriptions of operands in alternatives. */ }; /* Called once per compiler work to initialize some LRA data related to insns. */ static void init_insn_code_data_once (void) { memset (insn_code_data, 0, sizeof (insn_code_data)); } /* Called once per compiler work to finalize some LRA data related to insns. */ static void finish_insn_code_data_once (void) { for (unsigned int i = 0; i < NUM_INSN_CODES; i++) { if (insn_code_data[i] != NULL) { free (insn_code_data[i]); insn_code_data[i] = NULL; } } } /* Return static insn data, allocate and setup if necessary. Although dup_num is static data (it depends only on icode), to set it up we need to extract insn first. So recog_data should be valid for normal insn (ICODE >= 0) before the call. */ static struct lra_static_insn_data * get_static_insn_data (int icode, int nop, int ndup, int nalt) { struct lra_static_insn_data *data; size_t n_bytes; lra_assert (icode < (int) NUM_INSN_CODES); if (icode >= 0 && (data = insn_code_data[icode]) != NULL) return data; lra_assert (nop >= 0 && ndup >= 0 && nalt >= 0); n_bytes = sizeof (struct lra_static_insn_data) + sizeof (struct lra_operand_data) * nop + sizeof (int) * ndup; data = XNEWVAR (struct lra_static_insn_data, n_bytes); data->operand_alternative = NULL; data->n_operands = nop; data->n_dups = ndup; data->n_alternatives = nalt; data->operand = ((struct lra_operand_data *) ((char *) data + sizeof (struct lra_static_insn_data))); data->dup_num = ((int *) ((char *) data->operand + sizeof (struct lra_operand_data) * nop)); if (icode >= 0) { int i; insn_code_data[icode] = data; for (i = 0; i < nop; i++) { data->operand[i].constraint = insn_data[icode].operand[i].constraint; data->operand[i].mode = insn_data[icode].operand[i].mode; data->operand[i].strict_low = insn_data[icode].operand[i].strict_low; data->operand[i].is_operator = insn_data[icode].operand[i].is_operator; data->operand[i].type = (data->operand[i].constraint[0] == '=' ? OP_OUT : data->operand[i].constraint[0] == '+' ? OP_INOUT : OP_IN); data->operand[i].is_address = false; } for (i = 0; i < ndup; i++) data->dup_num[i] = recog_data.dup_num[i]; } return data; } /* The current length of the following array. */ int lra_insn_recog_data_len; /* Map INSN_UID -> the insn recog data (NULL if unknown). */ lra_insn_recog_data_t *lra_insn_recog_data; /* Alloc pool we allocate entries for lra_insn_recog_data from. */ static object_allocator<class lra_insn_recog_data> lra_insn_recog_data_pool ("insn recog data pool"); /* Initialize LRA data about insns. */ static void init_insn_recog_data (void) { lra_insn_recog_data_len = 0; lra_insn_recog_data = NULL; } /* Expand, if necessary, LRA data about insns. */ static void check_and_expand_insn_recog_data (int index) { int i, old; if (lra_insn_recog_data_len > index) return; old = lra_insn_recog_data_len; lra_insn_recog_data_len = index * 3U / 2; if (lra_insn_recog_data_len <= index) lra_insn_recog_data_len = index + 1; lra_insn_recog_data = XRESIZEVEC (lra_insn_recog_data_t, lra_insn_recog_data, lra_insn_recog_data_len); for (i = old; i < lra_insn_recog_data_len; i++) lra_insn_recog_data[i] = NULL; } /* Finish LRA DATA about insn. */ static void free_insn_recog_data (lra_insn_recog_data_t data) { if (data->operand_loc != NULL) free (data->operand_loc); if (data->dup_loc != NULL) free (data->dup_loc); if (data->arg_hard_regs != NULL) free (data->arg_hard_regs); if (data->icode < 0 && NONDEBUG_INSN_P (data->insn)) { if (data->insn_static_data->operand_alternative != NULL) free (const_cast <operand_alternative *> (data->insn_static_data->operand_alternative)); free_insn_regs (data->insn_static_data->hard_regs); free (data->insn_static_data); } free_insn_regs (data->regs); data->regs = NULL; lra_insn_recog_data_pool.remove (data); } /* Pools for copies. */ static object_allocator<lra_copy> lra_copy_pool ("lra copies"); /* Finish LRA data about all insns. */ static void finish_insn_recog_data (void) { int i; lra_insn_recog_data_t data; for (i = 0; i < lra_insn_recog_data_len; i++) if ((data = lra_insn_recog_data[i]) != NULL) free_insn_recog_data (data); finish_insn_regs (); lra_copy_pool.release (); lra_insn_reg_pool.release (); lra_insn_recog_data_pool.release (); free (lra_insn_recog_data); } /* Setup info about operands in alternatives of LRA DATA of insn. */ static void setup_operand_alternative (lra_insn_recog_data_t data, const operand_alternative *op_alt) { int i, j, nop, nalt; int icode = data->icode; struct lra_static_insn_data *static_data = data->insn_static_data; static_data->commutative = -1; nop = static_data->n_operands; nalt = static_data->n_alternatives; static_data->operand_alternative = op_alt; for (i = 0; i < nop; i++) { static_data->operand[i].early_clobber_alts = 0; static_data->operand[i].is_address = false; if (static_data->operand[i].constraint[0] == '%') { /* We currently only support one commutative pair of operands. */ if (static_data->commutative < 0) static_data->commutative = i; else lra_assert (icode < 0); /* Asm */ /* The last operand should not be marked commutative. */ lra_assert (i != nop - 1); } } for (j = 0; j < nalt; j++) for (i = 0; i < nop; i++, op_alt++) { if (op_alt->earlyclobber) static_data->operand[i].early_clobber_alts |= (alternative_mask) 1 << j; static_data->operand[i].is_address |= op_alt->is_address; } } /* Recursively process X and collect info about registers, which are not the insn operands, in X with TYPE (in/out/inout) and flag that it is early clobbered in the insn (EARLY_CLOBBER) and add the info to LIST. X is a part of insn given by DATA. Return the result list. */ static struct lra_insn_reg * collect_non_operand_hard_regs (rtx_insn *insn, rtx *x, lra_insn_recog_data_t data, struct lra_insn_reg *list, enum op_type type, bool early_clobber) { int i, j, regno, last; bool subreg_p; machine_mode mode; struct lra_insn_reg *curr; rtx op = *x; enum rtx_code code = GET_CODE (op); const char *fmt = GET_RTX_FORMAT (code); for (i = 0; i < data->insn_static_data->n_operands; i++) if (! data->insn_static_data->operand[i].is_operator && x == data->operand_loc[i]) /* It is an operand loc. Stop here. */ return list; for (i = 0; i < data->insn_static_data->n_dups; i++) if (x == data->dup_loc[i]) /* It is a dup loc. Stop here. */ return list; mode = GET_MODE (op); subreg_p = false; if (code == SUBREG) { mode = wider_subreg_mode (op); if (read_modify_subreg_p (op)) subreg_p = true; op = SUBREG_REG (op); code = GET_CODE (op); } if (REG_P (op)) { if ((regno = REGNO (op)) >= FIRST_PSEUDO_REGISTER) return list; /* Process all regs even unallocatable ones as we need info about all regs for rematerialization pass. */ for (last = end_hard_regno (mode, regno); regno < last; regno++) { for (curr = list; curr != NULL; curr = curr->next) if (curr->regno == regno && curr->subreg_p == subreg_p && curr->biggest_mode == mode) { if (curr->type != type) curr->type = OP_INOUT; if (early_clobber) curr->early_clobber_alts = ALL_ALTERNATIVES; break; } if (curr == NULL) { /* This is a new hard regno or the info cannot be integrated into the found structure. */ #ifdef STACK_REGS early_clobber = (early_clobber /* This clobber is to inform popping floating point stack only. */ && ! (FIRST_STACK_REG <= regno && regno <= LAST_STACK_REG)); #endif list = new_insn_reg (data->insn, regno, type, mode, subreg_p, early_clobber ? ALL_ALTERNATIVES : 0, list); } } return list; } switch (code) { case SET: list = collect_non_operand_hard_regs (insn, &SET_DEST (op), data, list, OP_OUT, false); list = collect_non_operand_hard_regs (insn, &SET_SRC (op), data, list, OP_IN, false); break; case CLOBBER: /* We treat clobber of non-operand hard registers as early clobber. */ list = collect_non_operand_hard_regs (insn, &XEXP (op, 0), data, list, OP_OUT, true); break; case PRE_INC: case PRE_DEC: case POST_INC: case POST_DEC: list = collect_non_operand_hard_regs (insn, &XEXP (op, 0), data, list, OP_INOUT, false); break; case PRE_MODIFY: case POST_MODIFY: list = collect_non_operand_hard_regs (insn, &XEXP (op, 0), data, list, OP_INOUT, false); list = collect_non_operand_hard_regs (insn, &XEXP (op, 1), data, list, OP_IN, false); break; default: fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { if (fmt[i] == 'e') list = collect_non_operand_hard_regs (insn, &XEXP (op, i), data, list, OP_IN, false); else if (fmt[i] == 'E') for (j = XVECLEN (op, i) - 1; j >= 0; j--) list = collect_non_operand_hard_regs (insn, &XVECEXP (op, i, j), data, list, OP_IN, false); } } return list; } /* Set up and return info about INSN. Set up the info if it is not set up yet. */ lra_insn_recog_data_t lra_set_insn_recog_data (rtx_insn *insn) { lra_insn_recog_data_t data; int i, n, icode; rtx **locs; unsigned int uid = INSN_UID (insn); struct lra_static_insn_data *insn_static_data; check_and_expand_insn_recog_data (uid); if (DEBUG_INSN_P (insn)) icode = -1; else { icode = INSN_CODE (insn); if (icode < 0) /* It might be a new simple insn which is not recognized yet. */ INSN_CODE (insn) = icode = recog_memoized (insn); } data = lra_insn_recog_data_pool.allocate (); lra_insn_recog_data[uid] = data; data->insn = insn; data->used_insn_alternative = LRA_UNKNOWN_ALT; data->asm_reloads_num = 0; data->icode = icode; data->regs = NULL; if (DEBUG_INSN_P (insn)) { data->dup_loc = NULL; data->arg_hard_regs = NULL; data->preferred_alternatives = ALL_ALTERNATIVES; if (DEBUG_BIND_INSN_P (insn)) { data->insn_static_data = &debug_bind_static_data; data->operand_loc = XNEWVEC (rtx *, 1); data->operand_loc[0] = &INSN_VAR_LOCATION_LOC (insn); } else if (DEBUG_MARKER_INSN_P (insn)) { data->insn_static_data = &debug_marker_static_data; data->operand_loc = NULL; } return data; } if (icode < 0) { int nop, nalt; machine_mode operand_mode[MAX_RECOG_OPERANDS]; const char *constraints[MAX_RECOG_OPERANDS]; nop = asm_noperands (PATTERN (insn)); data->operand_loc = data->dup_loc = NULL; nalt = 1; if (nop < 0) { /* It is a special insn like USE or CLOBBER. We should recognize any regular insn otherwise LRA can do nothing with this insn. */ gcc_assert (GET_CODE (PATTERN (insn)) == USE || GET_CODE (PATTERN (insn)) == CLOBBER || GET_CODE (PATTERN (insn)) == ASM_INPUT); data->insn_static_data = insn_static_data = get_static_insn_data (-1, 0, 0, nalt); } else { /* expand_asm_operands makes sure there aren't too many operands. */ lra_assert (nop <= MAX_RECOG_OPERANDS); if (nop != 0) data->operand_loc = XNEWVEC (rtx *, nop); /* Now get the operand values and constraints out of the insn. */ decode_asm_operands (PATTERN (insn), NULL, data->operand_loc, constraints, operand_mode, NULL); if (nop > 0) for (const char *p =constraints[0]; *p; p++) nalt += *p == ','; data->insn_static_data = insn_static_data = get_static_insn_data (-1, nop, 0, nalt); for (i = 0; i < nop; i++) { insn_static_data->operand[i].mode = operand_mode[i]; insn_static_data->operand[i].constraint = constraints[i]; insn_static_data->operand[i].strict_low = false; insn_static_data->operand[i].is_operator = false; insn_static_data->operand[i].is_address = false; } } for (i = 0; i < insn_static_data->n_operands; i++) insn_static_data->operand[i].type = (insn_static_data->operand[i].constraint[0] == '=' ? OP_OUT : insn_static_data->operand[i].constraint[0] == '+' ? OP_INOUT : OP_IN); data->preferred_alternatives = ALL_ALTERNATIVES; if (nop > 0) { operand_alternative *op_alt = XCNEWVEC (operand_alternative, nalt * nop); preprocess_constraints (nop, nalt, constraints, op_alt, data->operand_loc); setup_operand_alternative (data, op_alt); } } else { insn_extract (insn); data->insn_static_data = insn_static_data = get_static_insn_data (icode, insn_data[icode].n_operands, insn_data[icode].n_dups, insn_data[icode].n_alternatives); n = insn_static_data->n_operands; if (n == 0) locs = NULL; else { locs = XNEWVEC (rtx *, n); memcpy (locs, recog_data.operand_loc, n * sizeof (rtx *)); } data->operand_loc = locs; n = insn_static_data->n_dups; if (n == 0) locs = NULL; else { locs = XNEWVEC (rtx *, n); memcpy (locs, recog_data.dup_loc, n * sizeof (rtx *)); } data->dup_loc = locs; data->preferred_alternatives = get_preferred_alternatives (insn); const operand_alternative *op_alt = preprocess_insn_constraints (icode); if (!insn_static_data->operand_alternative) setup_operand_alternative (data, op_alt); else if (op_alt != insn_static_data->operand_alternative) insn_static_data->operand_alternative = op_alt; } if (GET_CODE (PATTERN (insn)) == CLOBBER || GET_CODE (PATTERN (insn)) == USE) insn_static_data->hard_regs = NULL; else insn_static_data->hard_regs = collect_non_operand_hard_regs (insn, &PATTERN (insn), data, NULL, OP_IN, false); data->arg_hard_regs = NULL; if (CALL_P (insn)) { bool use_p; rtx link; int n_hard_regs, regno, arg_hard_regs[FIRST_PSEUDO_REGISTER]; n_hard_regs = 0; /* Finding implicit hard register usage. We believe it will be not changed whatever transformations are used. Call insns are such example. */ for (link = CALL_INSN_FUNCTION_USAGE (insn); link != NULL_RTX; link = XEXP (link, 1)) if (((use_p = GET_CODE (XEXP (link, 0)) == USE) || GET_CODE (XEXP (link, 0)) == CLOBBER) && REG_P (XEXP (XEXP (link, 0), 0))) { regno = REGNO (XEXP (XEXP (link, 0), 0)); lra_assert (regno < FIRST_PSEUDO_REGISTER); /* It is an argument register. */ for (i = REG_NREGS (XEXP (XEXP (link, 0), 0)) - 1; i >= 0; i--) arg_hard_regs[n_hard_regs++] = regno + i + (use_p ? 0 : FIRST_PSEUDO_REGISTER); } if (n_hard_regs != 0) { arg_hard_regs[n_hard_regs++] = -1; data->arg_hard_regs = XNEWVEC (int, n_hard_regs); memcpy (data->arg_hard_regs, arg_hard_regs, sizeof (int) * n_hard_regs); } } /* Some output operand can be recognized only from the context not from the constraints which are empty in this case. Call insn may contain a hard register in set destination with empty constraint and extract_insn treats them as an input. */ for (i = 0; i < insn_static_data->n_operands; i++) { int j; rtx pat, set; struct lra_operand_data *operand = &insn_static_data->operand[i]; /* ??? Should we treat 'X' the same way. It looks to me that 'X' means anything and empty constraint means we do not care. */ if (operand->type != OP_IN || *operand->constraint != '\0' || operand->is_operator) continue; pat = PATTERN (insn); if (GET_CODE (pat) == SET) { if (data->operand_loc[i] != &SET_DEST (pat)) continue; } else if (GET_CODE (pat) == PARALLEL) { for (j = XVECLEN (pat, 0) - 1; j >= 0; j--) { set = XVECEXP (PATTERN (insn), 0, j); if (GET_CODE (set) == SET && &SET_DEST (set) == data->operand_loc[i]) break; } if (j < 0) continue; } else continue; operand->type = OP_OUT; } return data; } /* Return info about insn give by UID. The info should be already set up. */ static lra_insn_recog_data_t get_insn_recog_data_by_uid (int uid) { lra_insn_recog_data_t data; data = lra_insn_recog_data[uid]; lra_assert (data != NULL); return data; } /* Invalidate all info about insn given by its UID. */ static void invalidate_insn_recog_data (int uid) { lra_insn_recog_data_t data; data = lra_insn_recog_data[uid]; lra_assert (data != NULL); free_insn_recog_data (data); lra_insn_recog_data[uid] = NULL; } /* Update all the insn info about INSN. It is usually called when something in the insn was changed. Return the updated info. */ lra_insn_recog_data_t lra_update_insn_recog_data (rtx_insn *insn) { lra_insn_recog_data_t data; int n; unsigned int uid = INSN_UID (insn); struct lra_static_insn_data *insn_static_data; poly_int64 sp_offset = 0; check_and_expand_insn_recog_data (uid); if ((data = lra_insn_recog_data[uid]) != NULL && data->icode != INSN_CODE (insn)) { sp_offset = data->sp_offset; invalidate_insn_data_regno_info (data, insn, get_insn_freq (insn)); invalidate_insn_recog_data (uid); data = NULL; } if (data == NULL) { data = lra_get_insn_recog_data (insn); /* Initiate or restore SP offset. */ data->sp_offset = sp_offset; return data; } insn_static_data = data->insn_static_data; data->used_insn_alternative = LRA_UNKNOWN_ALT; if (DEBUG_INSN_P (insn)) return data; if (data->icode < 0) { int nop; machine_mode operand_mode[MAX_RECOG_OPERANDS]; const char *constraints[MAX_RECOG_OPERANDS]; nop = asm_noperands (PATTERN (insn)); if (nop >= 0) { lra_assert (nop == data->insn_static_data->n_operands); /* Now get the operand values and constraints out of the insn. */ decode_asm_operands (PATTERN (insn), NULL, data->operand_loc, constraints, operand_mode, NULL); if (flag_checking) for (int i = 0; i < nop; i++) lra_assert (insn_static_data->operand[i].mode == operand_mode[i] && insn_static_data->operand[i].constraint == constraints[i] && ! insn_static_data->operand[i].is_operator); } if (flag_checking) for (int i = 0; i < insn_static_data->n_operands; i++) lra_assert (insn_static_data->operand[i].type == (insn_static_data->operand[i].constraint[0] == '=' ? OP_OUT : insn_static_data->operand[i].constraint[0] == '+' ? OP_INOUT : OP_IN)); } else { insn_extract (insn); n = insn_static_data->n_operands; if (n != 0) memcpy (data->operand_loc, recog_data.operand_loc, n * sizeof (rtx *)); n = insn_static_data->n_dups; if (n != 0) memcpy (data->dup_loc, recog_data.dup_loc, n * sizeof (rtx *)); lra_assert (check_bool_attrs (insn)); } return data; } /* Set up that INSN is using alternative ALT now. */ void lra_set_used_insn_alternative (rtx_insn *insn, int alt) { lra_insn_recog_data_t data; data = lra_get_insn_recog_data (insn); data->used_insn_alternative = alt; } /* Set up that insn with UID is using alternative ALT now. The insn info should be already set up. */ void lra_set_used_insn_alternative_by_uid (int uid, int alt) { lra_insn_recog_data_t data; check_and_expand_insn_recog_data (uid); data = lra_insn_recog_data[uid]; lra_assert (data != NULL); data->used_insn_alternative = alt; } /* This page contains code dealing with common register info and pseudo copies. */ /* The size of the following array. */ static int reg_info_size; /* Common info about each register. */ class lra_reg *lra_reg_info; HARD_REG_SET hard_regs_spilled_into; /* Last register value. */ static int last_reg_value; /* Return new register value. */ static int get_new_reg_value (void) { return ++last_reg_value; } /* Vec referring to pseudo copies. */ static vec<lra_copy_t> copy_vec; /* Initialize I-th element of lra_reg_info. */ static inline void initialize_lra_reg_info_element (int i) { bitmap_initialize (&lra_reg_info[i].insn_bitmap, &reg_obstack); #ifdef STACK_REGS lra_reg_info[i].no_stack_p = false; #endif CLEAR_HARD_REG_SET (lra_reg_info[i].conflict_hard_regs); CLEAR_HARD_REG_SET (lra_reg_info[i].exclude_start_hard_regs); lra_reg_info[i].preferred_hard_regno1 = -1; lra_reg_info[i].preferred_hard_regno2 = -1; lra_reg_info[i].preferred_hard_regno_profit1 = 0; lra_reg_info[i].preferred_hard_regno_profit2 = 0; lra_reg_info[i].biggest_mode = VOIDmode; lra_reg_info[i].live_ranges = NULL; lra_reg_info[i].nrefs = lra_reg_info[i].freq = 0; lra_reg_info[i].last_reload = 0; lra_reg_info[i].restore_rtx = NULL_RTX; lra_reg_info[i].val = get_new_reg_value (); lra_reg_info[i].offset = 0; lra_reg_info[i].copies = NULL; } /* Initialize common reg info and copies. */ static void init_reg_info (void) { int i; last_reg_value = 0; reg_info_size = max_reg_num () * 3 / 2 + 1; lra_reg_info = XNEWVEC (class lra_reg, reg_info_size); for (i = 0; i < reg_info_size; i++) initialize_lra_reg_info_element (i); copy_vec.truncate (0); CLEAR_HARD_REG_SET (hard_regs_spilled_into); } /* Finish common reg info and copies. */ static void finish_reg_info (void) { int i; for (i = 0; i < reg_info_size; i++) bitmap_clear (&lra_reg_info[i].insn_bitmap); free (lra_reg_info); reg_info_size = 0; } /* Expand common reg info if it is necessary. */ static void expand_reg_info (void) { int i, old = reg_info_size; if (reg_info_size > max_reg_num ()) return; reg_info_size = max_reg_num () * 3 / 2 + 1; lra_reg_info = XRESIZEVEC (class lra_reg, lra_reg_info, reg_info_size); for (i = old; i < reg_info_size; i++) initialize_lra_reg_info_element (i); } /* Free all copies. */ void lra_free_copies (void) { lra_copy_t cp; while (copy_vec.length () != 0) { cp = copy_vec.pop (); lra_reg_info[cp->regno1].copies = lra_reg_info[cp->regno2].copies = NULL; lra_copy_pool.remove (cp); } } /* Create copy of two pseudos REGNO1 and REGNO2. The copy execution frequency is FREQ. */ void lra_create_copy (int regno1, int regno2, int freq) { bool regno1_dest_p; lra_copy_t cp; lra_assert (regno1 != regno2); regno1_dest_p = true; if (regno1 > regno2) { std::swap (regno1, regno2); regno1_dest_p = false; } cp = lra_copy_pool.allocate (); copy_vec.safe_push (cp); cp->regno1_dest_p = regno1_dest_p; cp->freq = freq; cp->regno1 = regno1; cp->regno2 = regno2; cp->regno1_next = lra_reg_info[regno1].copies; lra_reg_info[regno1].copies = cp; cp->regno2_next = lra_reg_info[regno2].copies; lra_reg_info[regno2].copies = cp; if (lra_dump_file != NULL) fprintf (lra_dump_file, " Creating copy r%d%sr%d@%d\n", regno1, regno1_dest_p ? "<-" : "->", regno2, freq); } /* Return N-th (0, 1, ...) copy. If there is no copy, return NULL. */ lra_copy_t lra_get_copy (int n) { if (n >= (int) copy_vec.length ()) return NULL; return copy_vec[n]; } /* This page contains code dealing with info about registers in insns. */ /* Process X of INSN recursively and add info (operand type is given by TYPE) about registers in X to the insn DATA. If X can be early clobbered, alternatives in which it can be early clobbered are given by EARLY_CLOBBER_ALTS. */ static void add_regs_to_insn_regno_info (lra_insn_recog_data_t data, rtx x, rtx_insn *insn, enum op_type type, alternative_mask early_clobber_alts) { int i, j, regno; bool subreg_p; machine_mode mode; const char *fmt; enum rtx_code code; struct lra_insn_reg *curr; code = GET_CODE (x); mode = GET_MODE (x); subreg_p = false; if (GET_CODE (x) == SUBREG) { mode = wider_subreg_mode (x); if (read_modify_subreg_p (x)) subreg_p = true; x = SUBREG_REG (x); code = GET_CODE (x); } if (REG_P (x)) { regno = REGNO (x); /* Process all regs even unallocatable ones as we need info about all regs for rematerialization pass. */ expand_reg_info (); if (bitmap_set_bit (&lra_reg_info[regno].insn_bitmap, INSN_UID (insn))) { data->regs = new_insn_reg (data->insn, regno, type, mode, subreg_p, early_clobber_alts, data->regs); return; } else { for (curr = data->regs; curr != NULL; curr = curr->next) if (curr->regno == regno) { if (curr->subreg_p != subreg_p || curr->biggest_mode != mode) /* The info cannot be integrated into the found structure. */ data->regs = new_insn_reg (data->insn, regno, type, mode, subreg_p, early_clobber_alts, data->regs); else { if (curr->type != type) curr->type = OP_INOUT; curr->early_clobber_alts |= early_clobber_alts; } return; } gcc_unreachable (); } } switch (code) { case SET: add_regs_to_insn_regno_info (data, SET_DEST (x), insn, OP_OUT, 0); add_regs_to_insn_regno_info (data, SET_SRC (x), insn, OP_IN, 0); break; case CLOBBER: /* We treat clobber of non-operand hard registers as early clobber. */ add_regs_to_insn_regno_info (data, XEXP (x, 0), insn, OP_OUT, ALL_ALTERNATIVES); break; case PRE_INC: case PRE_DEC: case POST_INC: case POST_DEC: add_regs_to_insn_regno_info (data, XEXP (x, 0), insn, OP_INOUT, 0); break; case PRE_MODIFY: case POST_MODIFY: add_regs_to_insn_regno_info (data, XEXP (x, 0), insn, OP_INOUT, 0); add_regs_to_insn_regno_info (data, XEXP (x, 1), insn, OP_IN, 0); break; default: if ((code != PARALLEL && code != EXPR_LIST) || type != OP_OUT) /* Some targets place small structures in registers for return values of functions, and those registers are wrapped in PARALLEL that we may see as the destination of a SET. Here is an example: (call_insn 13 12 14 2 (set (parallel:BLK [ (expr_list:REG_DEP_TRUE (reg:DI 0 ax) (const_int 0 [0])) (expr_list:REG_DEP_TRUE (reg:DI 1 dx) (const_int 8 [0x8])) ]) (call (mem:QI (symbol_ref:DI (... */ type = OP_IN; fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { if (fmt[i] == 'e') add_regs_to_insn_regno_info (data, XEXP (x, i), insn, type, 0); else if (fmt[i] == 'E') { for (j = XVECLEN (x, i) - 1; j >= 0; j--) add_regs_to_insn_regno_info (data, XVECEXP (x, i, j), insn, type, 0); } } } } /* Return execution frequency of INSN. */ static int get_insn_freq (rtx_insn *insn) { basic_block bb = BLOCK_FOR_INSN (insn); gcc_checking_assert (bb != NULL); return REG_FREQ_FROM_BB (bb); } /* Invalidate all reg info of INSN with DATA and execution frequency FREQ. Update common info about the invalidated registers. */ static void invalidate_insn_data_regno_info (lra_insn_recog_data_t data, rtx_insn *insn, int freq) { int uid; bool debug_p; unsigned int i; struct lra_insn_reg *ir, *next_ir; uid = INSN_UID (insn); debug_p = DEBUG_INSN_P (insn); for (ir = data->regs; ir != NULL; ir = next_ir) { i = ir->regno; next_ir = ir->next; lra_insn_reg_pool.remove (ir); bitmap_clear_bit (&lra_reg_info[i].insn_bitmap, uid); if (i >= FIRST_PSEUDO_REGISTER && ! debug_p) { lra_reg_info[i].nrefs--; lra_reg_info[i].freq -= freq; lra_assert (lra_reg_info[i].nrefs >= 0 && lra_reg_info[i].freq >= 0); } } data->regs = NULL; } /* Invalidate all reg info of INSN. Update common info about the invalidated registers. */ void lra_invalidate_insn_regno_info (rtx_insn *insn) { invalidate_insn_data_regno_info (lra_get_insn_recog_data (insn), insn, get_insn_freq (insn)); } /* Update common reg info from reg info of insn given by its DATA and execution frequency FREQ. */ static void setup_insn_reg_info (lra_insn_recog_data_t data, int freq) { unsigned int i; struct lra_insn_reg *ir; for (ir = data->regs; ir != NULL; ir = ir->next) if ((i = ir->regno) >= FIRST_PSEUDO_REGISTER) { lra_reg_info[i].nrefs++; lra_reg_info[i].freq += freq; } } /* Set up insn reg info of INSN. Update common reg info from reg info of INSN. */ void lra_update_insn_regno_info (rtx_insn *insn) { int i, freq; lra_insn_recog_data_t data; struct lra_static_insn_data *static_data; enum rtx_code code; rtx link; if (! INSN_P (insn)) return; data = lra_get_insn_recog_data (insn); static_data = data->insn_static_data; freq = NONDEBUG_INSN_P (insn) ? get_insn_freq (insn) : 0; invalidate_insn_data_regno_info (data, insn, freq); for (i = static_data->n_operands - 1; i >= 0; i--) add_regs_to_insn_regno_info (data, *data->operand_loc[i], insn, static_data->operand[i].type, static_data->operand[i].early_clobber_alts); if ((code = GET_CODE (PATTERN (insn))) == CLOBBER || code == USE) add_regs_to_insn_regno_info (data, XEXP (PATTERN (insn), 0), insn, code == USE ? OP_IN : OP_OUT, 0); if (CALL_P (insn)) /* On some targets call insns can refer to pseudos in memory in CALL_INSN_FUNCTION_USAGE list. Process them in order to consider their occurrences in calls for different transformations (e.g. inheritance) with given pseudos. */ for (link = CALL_INSN_FUNCTION_USAGE (insn); link != NULL_RTX; link = XEXP (link, 1)) { code = GET_CODE (XEXP (link, 0)); if ((code == USE || code == CLOBBER) && MEM_P (XEXP (XEXP (link, 0), 0))) add_regs_to_insn_regno_info (data, XEXP (XEXP (link, 0), 0), insn, code == USE ? OP_IN : OP_OUT, 0); } if (NONDEBUG_INSN_P (insn)) setup_insn_reg_info (data, freq); } /* Return reg info of insn given by it UID. */ struct lra_insn_reg * lra_get_insn_regs (int uid) { lra_insn_recog_data_t data; data = get_insn_recog_data_by_uid (uid); return data->regs; } /* Recursive hash function for RTL X. */ hashval_t lra_rtx_hash (rtx x) { int i, j; enum rtx_code code; const char *fmt; hashval_t val = 0; if (x == 0) return val; code = GET_CODE (x); val += (int) code + 4095; /* Some RTL can be compared nonrecursively. */ switch (code) { case REG: return val + REGNO (x); case LABEL_REF: return iterative_hash_object (XEXP (x, 0), val); case SYMBOL_REF: return iterative_hash_object (XSTR (x, 0), val); case SCRATCH: case CONST_DOUBLE: case CONST_VECTOR: return val; case CONST_INT: return val + UINTVAL (x); case SUBREG: val += lra_rtx_hash (SUBREG_REG (x)); for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i) val += SUBREG_BYTE (x).coeffs[i]; return val; default: break; } /* Hash the elements. */ fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { switch (fmt[i]) { case 'w': val += XWINT (x, i); break; case 'n': case 'i': val += XINT (x, i); break; case 'L': val += XLOC (x, i); break; case 'V': case 'E': val += XVECLEN (x, i); for (j = 0; j < XVECLEN (x, i); j++) val += lra_rtx_hash (XVECEXP (x, i, j)); break; case 'e': val += lra_rtx_hash (XEXP (x, i)); break; case 'S': case 's': val += htab_hash_string (XSTR (x, i)); break; case 'u': case '0': case 't': break; /* It is believed that rtx's at this level will never contain anything but integers and other rtx's, except for within LABEL_REFs and SYMBOL_REFs. */ default: abort (); } } return val; } /* This page contains code dealing with stack of the insns which should be processed by the next constraint pass. */ /* Bitmap used to put an insn on the stack only in one exemplar. */ static sbitmap lra_constraint_insn_stack_bitmap; /* The stack itself. */ vec<rtx_insn *> lra_constraint_insn_stack; /* Put INSN on the stack. If ALWAYS_UPDATE is true, always update the reg info for INSN, otherwise only update it if INSN is not already on the stack. */ static inline void lra_push_insn_1 (rtx_insn *insn, bool always_update) { unsigned int uid = INSN_UID (insn); if (always_update) lra_update_insn_regno_info (insn); if (uid >= SBITMAP_SIZE (lra_constraint_insn_stack_bitmap)) lra_constraint_insn_stack_bitmap = sbitmap_resize (lra_constraint_insn_stack_bitmap, 3 * uid / 2, 0); if (bitmap_bit_p (lra_constraint_insn_stack_bitmap, uid)) return; bitmap_set_bit (lra_constraint_insn_stack_bitmap, uid); if (! always_update) lra_update_insn_regno_info (insn); lra_constraint_insn_stack.safe_push (insn); } /* Put INSN on the stack. */ void lra_push_insn (rtx_insn *insn) { lra_push_insn_1 (insn, false); } /* Put INSN on the stack and update its reg info. */ void lra_push_insn_and_update_insn_regno_info (rtx_insn *insn) { lra_push_insn_1 (insn, true); } /* Put insn with UID on the stack. */ void lra_push_insn_by_uid (unsigned int uid) { lra_push_insn (lra_insn_recog_data[uid]->insn); } /* Take the last-inserted insns off the stack and return it. */ rtx_insn * lra_pop_insn (void) { rtx_insn *insn = lra_constraint_insn_stack.pop (); bitmap_clear_bit (lra_constraint_insn_stack_bitmap, INSN_UID (insn)); return insn; } /* Return the current size of the insn stack. */ unsigned int lra_insn_stack_length (void) { return lra_constraint_insn_stack.length (); } /* Push insns FROM to TO (excluding it) going in reverse order. */ static void push_insns (rtx_insn *from, rtx_insn *to) { rtx_insn *insn; if (from == NULL_RTX) return; for (insn = from; insn != to; insn = PREV_INSN (insn)) if (INSN_P (insn)) lra_push_insn (insn); } /* Set up and return sp offset for insns in range [FROM, LAST]. The offset is taken from the BB insn before FROM after simulating its effects, or zero if there is no such insn. */ static poly_int64 setup_sp_offset (rtx_insn *from, rtx_insn *last) { rtx_insn *before = prev_nonnote_nondebug_insn_bb (from); poly_int64 offset = 0; if (before && INSN_P (before)) offset = lra_update_sp_offset (PATTERN (before), lra_get_insn_recog_data (before)->sp_offset); for (rtx_insn *insn = from; insn != NEXT_INSN (last); insn = NEXT_INSN (insn)) { lra_get_insn_recog_data (insn)->sp_offset = offset; offset = lra_update_sp_offset (PATTERN (insn), offset); } return offset; } /* Dump all func insns in a slim form. */ void lra_dump_insns (FILE *f) { dump_rtl_slim (f, get_insns (), NULL, -1, 0); } /* Dump all func insns in a slim form with TITLE when the dump file is open and lra_verbose >=7. */ void lra_dump_insns_if_possible (const char *title) { if (lra_dump_file == NULL || lra_verbose < 7) return; fprintf (lra_dump_file, "%s:", title); lra_dump_insns (lra_dump_file); } /* Emit insns BEFORE before INSN and insns AFTER after INSN. Put the insns onto the stack. Print about emitting the insns with TITLE. */ void lra_process_new_insns (rtx_insn *insn, rtx_insn *before, rtx_insn *after, const char *title) { if (before == NULL_RTX && after == NULL_RTX) return; if (lra_dump_file != NULL) { dump_insn_slim (lra_dump_file, insn); if (before != NULL_RTX) { fprintf (lra_dump_file," %s before:\n", title); dump_rtl_slim (lra_dump_file, before, NULL, -1, 0); } } if (before != NULL_RTX) { if (cfun->can_throw_non_call_exceptions) copy_reg_eh_region_note_forward (insn, before, NULL); emit_insn_before (before, insn); poly_int64 old_sp_offset = lra_get_insn_recog_data (insn)->sp_offset; poly_int64 new_sp_offset = setup_sp_offset (before, PREV_INSN (insn)); if (maybe_ne (old_sp_offset, new_sp_offset)) { if (lra_dump_file != NULL) { fprintf (lra_dump_file, " Changing sp offset from "); print_dec (old_sp_offset, lra_dump_file); fprintf (lra_dump_file, " to "); print_dec (new_sp_offset, lra_dump_file); fprintf (lra_dump_file, " for insn"); dump_rtl_slim (lra_dump_file, insn, NULL, -1, 0); } lra_get_insn_recog_data (insn)->sp_offset = new_sp_offset; eliminate_regs_in_insn (insn, false, false, old_sp_offset - new_sp_offset); lra_push_insn (insn); } push_insns (PREV_INSN (insn), PREV_INSN (before)); } if (after != NULL_RTX) { if (cfun->can_throw_non_call_exceptions) copy_reg_eh_region_note_forward (insn, after, NULL); if (! JUMP_P (insn)) { rtx_insn *last; if (lra_dump_file != NULL) { fprintf (lra_dump_file, " %s after:\n", title); dump_rtl_slim (lra_dump_file, after, NULL, -1, 0); } for (last = after; NEXT_INSN (last) != NULL_RTX; last = NEXT_INSN (last)) ; emit_insn_after (after, insn); push_insns (last, insn); setup_sp_offset (after, last); } else { /* Put output reload insns on successor BBs: */ edge_iterator ei; edge e; FOR_EACH_EDGE (e, ei, BLOCK_FOR_INSN (insn)->succs) if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) { /* We already made the edge no-critical in ira.cc::ira */ lra_assert (!EDGE_CRITICAL_P (e)); rtx_insn *curr, *tmp = BB_HEAD (e->dest); if (LABEL_P (tmp)) tmp = NEXT_INSN (tmp); if (NOTE_INSN_BASIC_BLOCK_P (tmp)) tmp = NEXT_INSN (tmp); /* Do not put reload insns if it is the last BB without actual insns. */ if (tmp == NULL) continue; start_sequence (); for (curr = after; curr != NULL_RTX; curr = NEXT_INSN (curr)) emit_insn (copy_insn (PATTERN (curr))); rtx_insn *copy = get_insns (), *last = get_last_insn (); end_sequence (); if (lra_dump_file != NULL) { fprintf (lra_dump_file, " %s after in bb%d:\n", title, e->dest->index); dump_rtl_slim (lra_dump_file, copy, NULL, -1, 0); } /* Use the right emit func for setting up BB_END/BB_HEAD: */ if (BB_END (e->dest) == PREV_INSN (tmp)) emit_insn_after_noloc (copy, PREV_INSN (tmp), e->dest); else emit_insn_before_noloc (copy, tmp, e->dest); push_insns (last, PREV_INSN (copy)); setup_sp_offset (copy, last); /* We can ignore BB live info here as it and reg notes will be updated before the next assignment sub-pass. */ } } } if (lra_dump_file != NULL) fprintf (lra_dump_file, "\n"); if (cfun->can_throw_non_call_exceptions) { rtx note = find_reg_note (insn, REG_EH_REGION, NULL_RTX); if (note && !insn_could_throw_p (insn)) remove_note (insn, note); } } /* Replace all references to register OLD_REGNO in *LOC with pseudo register NEW_REG. Try to simplify subreg of constant if SUBREG_P. DEBUG_P is if LOC is within a DEBUG_INSN. Return true if any change was made. */ bool lra_substitute_pseudo (rtx *loc, int old_regno, rtx new_reg, bool subreg_p, bool debug_p) { rtx x = *loc; bool result = false; enum rtx_code code; const char *fmt; int i, j; if (x == NULL_RTX) return false; code = GET_CODE (x); if (code == SUBREG && subreg_p) { rtx subst, inner = SUBREG_REG (x); /* Transform subreg of constant while we still have inner mode of the subreg. The subreg internal should not be an insn operand. */ if (REG_P (inner) && (int) REGNO (inner) == old_regno && CONSTANT_P (new_reg) && (subst = simplify_subreg (GET_MODE (x), new_reg, GET_MODE (inner), SUBREG_BYTE (x))) != NULL_RTX) { *loc = subst; return true; } } else if (code == REG && (int) REGNO (x) == old_regno) { machine_mode mode = GET_MODE (x); machine_mode inner_mode = GET_MODE (new_reg); if (mode != inner_mode && ! (CONST_SCALAR_INT_P (new_reg) && SCALAR_INT_MODE_P (mode))) { poly_uint64 offset = 0; if (partial_subreg_p (mode, inner_mode) && SCALAR_INT_MODE_P (inner_mode)) offset = subreg_lowpart_offset (mode, inner_mode); if (debug_p) new_reg = gen_rtx_raw_SUBREG (mode, new_reg, offset); else new_reg = gen_rtx_SUBREG (mode, new_reg, offset); } *loc = new_reg; return true; } /* Scan all the operand sub-expressions. */ fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { if (fmt[i] == 'e') { if (debug_p && i == 0 && (code == SUBREG || code == ZERO_EXTEND || code == SIGN_EXTEND || code == FLOAT || code == UNSIGNED_FLOAT)) { rtx y = XEXP (x, 0); if (lra_substitute_pseudo (&y, old_regno, new_reg, subreg_p, debug_p)) { result = true; if (CONST_SCALAR_INT_P (y)) { if (code == SUBREG) y = simplify_subreg (GET_MODE (x), y, GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x)); else y = simplify_unary_operation (code, GET_MODE (x), y, GET_MODE (XEXP (x, 0))); if (y) *loc = y; else *loc = gen_rtx_CLOBBER (GET_MODE (x), const0_rtx); } else XEXP (x, 0) = y; } } else if (lra_substitute_pseudo (&XEXP (x, i), old_regno, new_reg, subreg_p, debug_p)) result = true; } else if (fmt[i] == 'E') { for (j = XVECLEN (x, i) - 1; j >= 0; j--) if (lra_substitute_pseudo (&XVECEXP (x, i, j), old_regno, new_reg, subreg_p, debug_p)) result = true; } } return result; } /* Call lra_substitute_pseudo within an insn. Try to simplify subreg of constant if SUBREG_P. This won't update the insn ptr, just the contents of the insn. */ bool lra_substitute_pseudo_within_insn (rtx_insn *insn, int old_regno, rtx new_reg, bool subreg_p) { rtx loc = insn; return lra_substitute_pseudo (&loc, old_regno, new_reg, subreg_p, DEBUG_INSN_P (insn)); } /* Return new register of the same mode as ORIGINAL of class ALL_REGS. Used in ira_remove_scratches. */ static rtx get_scratch_reg (rtx original) { return lra_create_new_reg (GET_MODE (original), original, ALL_REGS, NULL, NULL); } /* Remove all insn scratches in INSN. */ static void remove_insn_scratches (rtx_insn *insn) { if (ira_remove_insn_scratches (insn, true, lra_dump_file, get_scratch_reg)) df_insn_rescan (insn); } /* Remove all insn scratches in the current function. */ static void remove_scratches (void) { basic_block bb; rtx_insn *insn; FOR_EACH_BB_FN (bb, cfun) FOR_BB_INSNS (bb, insn) if (INSN_P (insn)) remove_insn_scratches (insn); } /* Function checks RTL for correctness. If FINAL_P is true, it is done at the end of LRA and the check is more rigorous. */ static void check_rtl (bool final_p) { basic_block bb; rtx_insn *insn; lra_assert (! final_p || reload_completed); FOR_EACH_BB_FN (bb, cfun) FOR_BB_INSNS (bb, insn) if (NONDEBUG_INSN_P (insn) && GET_CODE (PATTERN (insn)) != USE && GET_CODE (PATTERN (insn)) != CLOBBER && GET_CODE (PATTERN (insn)) != ASM_INPUT) { if (final_p) { extract_constrain_insn (insn); continue; } /* LRA code is based on assumption that all addresses can be correctly decomposed. LRA can generate reloads for decomposable addresses. The decomposition code checks the correctness of the addresses. So we don't need to check the addresses here. Don't call insn_invalid_p here, it can change the code at this stage. */ if (recog_memoized (insn) < 0 && asm_noperands (PATTERN (insn)) < 0) fatal_insn_not_found (insn); } } /* Determine if the current function has an exception receiver block that reaches the exit block via non-exceptional edges */ static bool has_nonexceptional_receiver (void) { edge e; edge_iterator ei; basic_block *tos, *worklist, bb; /* If we're not optimizing, then just err on the safe side. */ if (!optimize) return true; /* First determine which blocks can reach exit via normal paths. */ tos = worklist = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) + 1); FOR_EACH_BB_FN (bb, cfun) bb->flags &= ~BB_REACHABLE; /* Place the exit block on our worklist. */ EXIT_BLOCK_PTR_FOR_FN (cfun)->flags |= BB_REACHABLE; *tos++ = EXIT_BLOCK_PTR_FOR_FN (cfun); /* Iterate: find everything reachable from what we've already seen. */ while (tos != worklist) { bb = *--tos; FOR_EACH_EDGE (e, ei, bb->preds) if (e->flags & EDGE_ABNORMAL) { free (worklist); return true; } else { basic_block src = e->src; if (!(src->flags & BB_REACHABLE)) { src->flags |= BB_REACHABLE; *tos++ = src; } } } free (worklist); /* No exceptional block reached exit unexceptionally. */ return false; } /* Remove all REG_DEAD and REG_UNUSED notes and regenerate REG_INC. We change pseudos by hard registers without notification of DF and that can make the notes obsolete. DF-infrastructure does not deal with REG_INC notes -- so we should regenerate them here. */ static void update_inc_notes (void) { rtx *pnote; basic_block bb; rtx_insn *insn; FOR_EACH_BB_FN (bb, cfun) FOR_BB_INSNS (bb, insn) if (NONDEBUG_INSN_P (insn)) { pnote = &REG_NOTES (insn); while (*pnote != 0) { if (REG_NOTE_KIND (*pnote) == REG_DEAD || REG_NOTE_KIND (*pnote) == REG_UNUSED || REG_NOTE_KIND (*pnote) == REG_INC) *pnote = XEXP (*pnote, 1); else pnote = &XEXP (*pnote, 1); } if (AUTO_INC_DEC) add_auto_inc_notes (insn, PATTERN (insn)); } } /* Set to true while in LRA. */ bool lra_in_progress = false; /* Start of pseudo regnos before the LRA. */ int lra_new_regno_start; /* Start of reload pseudo regnos before the new spill pass. */ int lra_constraint_new_regno_start; /* Avoid spilling pseudos with regno more than the following value if it is possible. */ int lra_bad_spill_regno_start; /* A pseudo of Pmode. */ rtx lra_pmode_pseudo; /* Inheritance pseudo regnos before the new spill pass. */ bitmap_head lra_inheritance_pseudos; /* Split regnos before the new spill pass. */ bitmap_head lra_split_regs; /* Reload pseudo regnos before the new assignment pass which still can be spilled after the assignment pass as memory is also accepted in insns for the reload pseudos. */ bitmap_head lra_optional_reload_pseudos; /* Pseudo regnos used for subreg reloads before the new assignment pass. Such pseudos still can be spilled after the assignment pass. */ bitmap_head lra_subreg_reload_pseudos; /* File used for output of LRA debug information. */ FILE *lra_dump_file; /* How verbose should be the debug information. */ int lra_verbose; /* True if we split hard reg after the last constraint sub-pass. */ bool lra_hard_reg_split_p; /* True if we found an asm error. */ bool lra_asm_error_p; /* True if we should try spill into registers of different classes instead of memory. */ bool lra_reg_spill_p; /* Set up value LRA_REG_SPILL_P. */ static void setup_reg_spill_flag (void) { int cl, mode; if (targetm.spill_class != NULL) for (cl = 0; cl < (int) LIM_REG_CLASSES; cl++) for (mode = 0; mode < MAX_MACHINE_MODE; mode++) if (targetm.spill_class ((enum reg_class) cl, (machine_mode) mode) != NO_REGS) { lra_reg_spill_p = true; return; } lra_reg_spill_p = false; } /* True if the current function is too big to use regular algorithms in LRA. In other words, we should use simpler and faster algorithms in LRA. It also means we should not worry about generation code for caller saves. The value is set up in IRA. */ bool lra_simple_p; /* Major LRA entry function. F is a file should be used to dump LRA debug info with given verbosity. */ void lra (FILE *f, int verbose) { int i; bool live_p, inserted_p; lra_dump_file = f; lra_verbose = verbose; lra_asm_error_p = false; lra_pmode_pseudo = gen_reg_rtx (Pmode); timevar_push (TV_LRA); /* Make sure that the last insn is a note. Some subsequent passes need it. */ emit_note (NOTE_INSN_DELETED); lra_no_alloc_regs = ira_no_alloc_regs; init_reg_info (); expand_reg_info (); init_insn_recog_data (); /* Some quick check on RTL generated by previous passes. */ if (flag_checking) check_rtl (false); lra_in_progress = true; lra_live_range_iter = lra_coalesce_iter = lra_constraint_iter = 0; lra_assignment_iter = lra_assignment_iter_after_spill = 0; lra_inheritance_iter = lra_undo_inheritance_iter = 0; lra_rematerialization_iter = 0; setup_reg_spill_flag (); /* Function remove_scratches can creates new pseudos for clobbers -- so set up lra_constraint_new_regno_start before its call to permit changing reg classes for pseudos created by this simplification. */ lra_constraint_new_regno_start = lra_new_regno_start = max_reg_num (); lra_bad_spill_regno_start = INT_MAX; remove_scratches (); /* A function that has a non-local label that can reach the exit block via non-exceptional paths must save all call-saved registers. */ if (cfun->has_nonlocal_label && has_nonexceptional_receiver ()) crtl->saves_all_registers = 1; if (crtl->saves_all_registers) for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) if (!crtl->abi->clobbers_full_reg_p (i) && !fixed_regs[i] && !LOCAL_REGNO (i)) df_set_regs_ever_live (i, true); /* We don't DF from now and avoid its using because it is to expensive when a lot of RTL changes are made. */ df_set_flags (DF_NO_INSN_RESCAN); lra_constraint_insn_stack.create (get_max_uid ()); lra_constraint_insn_stack_bitmap = sbitmap_alloc (get_max_uid ()); bitmap_clear (lra_constraint_insn_stack_bitmap); lra_live_ranges_init (); lra_constraints_init (); lra_curr_reload_num = 0; push_insns (get_last_insn (), NULL); /* It is needed for the 1st coalescing. */ bitmap_initialize (&lra_inheritance_pseudos, &reg_obstack); bitmap_initialize (&lra_split_regs, &reg_obstack); bitmap_initialize (&lra_optional_reload_pseudos, &reg_obstack); bitmap_initialize (&lra_subreg_reload_pseudos, &reg_obstack); live_p = false; if (maybe_ne (get_frame_size (), 0) && crtl->stack_alignment_needed) /* If we have a stack frame, we must align it now. The stack size may be a part of the offset computation for register elimination. */ assign_stack_local (BLKmode, 0, crtl->stack_alignment_needed); lra_init_equiv (); for (;;) { for (;;) { bool reloads_p = lra_constraints (lra_constraint_iter == 0); /* Constraint transformations may result in that eliminable hard regs become uneliminable and pseudos which use them should be spilled. It is better to do it before pseudo assignments. For example, rs6000 can make RS6000_PIC_OFFSET_TABLE_REGNUM uneliminable if we started to use a constant pool. */ lra_eliminate (false, false); /* We should try to assign hard registers to scratches even if there were no RTL transformations in lra_constraints. Also we should check IRA assignments on the first iteration as they can be wrong because of early clobbers operands which are ignored in IRA. */ if (! reloads_p && lra_constraint_iter > 1) { /* Stack is not empty here only when there are changes during the elimination sub-pass. */ if (bitmap_empty_p (lra_constraint_insn_stack_bitmap)) break; else /* If there are no reloads but changing due elimination, restart the constraint sub-pass first. */ continue; } /* Do inheritance only for regular algorithms. */ if (! lra_simple_p) lra_inheritance (); if (live_p) lra_clear_live_ranges (); bool fails_p; lra_hard_reg_split_p = false; int split_fails_num = 0; do { /* We need live ranges for lra_assign -- so build them. But don't remove dead insns or change global live info as we can undo inheritance transformations after inheritance pseudo assigning. */ lra_create_live_ranges (true, !lra_simple_p); live_p = true; /* If we don't spill non-reload and non-inheritance pseudos, there is no sense to run memory-memory move coalescing. If inheritance pseudos were spilled, the memory-memory moves involving them will be removed by pass undoing inheritance. */ if (lra_simple_p || lra_hard_reg_split_p) lra_assign (fails_p); else { bool spill_p = !lra_assign (fails_p); if (lra_undo_inheritance ())


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